Digging this old thread up to say there is a scan of Cnósach focal ó Bhaile Bhúirne online. Version on archive, https://archive.org/details/cnosachfocalobha0000unse, is unavailable now, unfortunately… But you can try your luck in any of the many 'unofficial' online libraries out there. (In particular an archive belonging to a certain Anna.) Just search for the name of the file.
If we consider Mícheál Ó Briain to be the author, and Brian Ó Cuív a mere editor, as indeed information to be found on the book suggests, i.e. "Mícheál Ó Briain a bhailigh, Brian Ó Cuív a chóraigh", then the work is out of copyright so you're free to reproduce it. (This is not intended to convey or constitute legal advice.)